Highly stable piezoelectrically tunable optical cavities

TL;DR

This paper demonstrates highly stable, tunable optical cavities with piezo actuators made from various materials, achieving exceptional frequency stability and tunability, and introduces a novel cavity design with a hermetic seal for advanced spectroscopy applications.

Contribution

The paper presents a new cavity design with piezo actuators that offers improved stability, tunability, and hermetic sealing for optical frequency references.

Findings

Frequency stability better than 1 x 10^{-14}

Electrical tuning over > 1.5 GHz with minimal stability loss

Novel hermetically sealed cavity design

Abstract

We have implemented highly stable and tunable frequency references using optical high finesse cavities which incorporate a piezo actuator. As piezo material we used ceramic PZT, crystalline quartz, or PZN-PT single crystals. Lasers locked to these cavities show a relative frequency stability better than 1 x 10^{-14}, which is most likely not limited by the piezo actuators. The piezo cavities can be electrically tuned over more than one free spectral range (> 1.5 GHz) with only a minor decrease in frequency stability. Furthermore, we present a novel cavity design, where the piezo actuator is prestressed between the cavity spacer components. This design features a hermetically sealable intra cavity volume suitable for, e.g., cavity enhanced spectroscopy.